⚡ Bolt: Optimize and fix string replacement

[google-labs-jules]

This pull request optimizes the stringReplace function and fixes a bug in its non-overlapping replacement logic. By delegating to the StringHelpers::replace_all function, it avoids repeated memory reallocations, leading to a significant performance improvement. Additionally, it corrects a flaw in the original implementation that produced incorrect results in certain scenarios.

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PR created automatically by Jules for task 15846451580282937914 started by @Nelson-numerical-software

[google-labs-jules]

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